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About Granular restore from backup to tape

Marianne
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Disclaimer:
Please ignore any badges next to my name Smiley Embarassed . My expertise is NetBackup, with very basic BE knowledge.

Our customer is backing up a virtual fileserver (VMware) directly to tape.

Question:
To restore a few individual files, do we need to stage to disk (like with Exchange), or can the files be extracted from tape without staging?

 

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Accepted Solutions

pkh
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Yes. Staging is required if the backup is on tape.  This is because the entire VM is stored on tape, not the individual files.  If you restore from tape, you need to allow time for the staging and ensure that there is sufficient free space for the entire VM.  Alternatively, you can duplicate the backup set to disk and then restore the files from the disk backup set.

You can backup the VM as if it is a physical machine, but you loose the ability to restore it as a VM.  If you need to restore the entire VM, in this case, you need to create a new VM and then proceed to restore to this new VM as if it is a physical machine, whereas if it is backed up as a VM, then you just need to restore it as VM.

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CraigV
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Hi Marianne, It has always worked like this. I think there might have been a product feature request put in during the old Symantec days when this first came out but nothing was done about it. If 1 product in the stack can do it, they should be able to retrofit this along the line for the other. Not to be. So you need as much disk space available for staging as your largest VM. Otherwise get them to buy cheaper iSCSI disk and attach this way. It will work very well if paired with 10GbE network cards. Cheers, and keep well, Craig

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Marianne
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I found this section of the Best Practice Guide:

https://www.veritas.com/support/en_US/doc/72686287-131623464-0/v70445037-131623464

So, sections that apply to our customer's situation:

GRT is enabled by default for the following resources. It can be enabled or disabled in the Backup Options dialog when you create a backup job:

....
VMware
....
.....

You must use a staging location for GRT-enabled jobs in the following scenarios:
...
You back up to tape.

What worries me is this section and the amount of space required to restore a folder or some files:

Tape backups require a staging location that is at least as large as the data that you back up. Backup Exec extracts the granular data to the staging location while it is being cataloged. When you restore granular data from a tape backup, you must specify a staging location to store all of the backup sets that are required for the restore job as well as a separate staging location of at least 1 GB for the GRT processing.

I don't know the exact size of the customer's fileserver - let's say it is somewhere between 5 and 10TB.
This means that the VMDK backup will reflect the same size - between 5 and 10TB.

What does this mean for a granular restore?
Do we really need 5 - 10TB storage space for staging?
Do we need to plan for time to perform the staging before the restore can start?

If this is how individual file restore works for VMware backup on tape, will it be better to install the agent on the fileserver and perform backup as if this is a physical server?

pkh
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Yes. Staging is required if the backup is on tape.  This is because the entire VM is stored on tape, not the individual files.  If you restore from tape, you need to allow time for the staging and ensure that there is sufficient free space for the entire VM.  Alternatively, you can duplicate the backup set to disk and then restore the files from the disk backup set.

You can backup the VM as if it is a physical machine, but you loose the ability to restore it as a VM.  If you need to restore the entire VM, in this case, you need to create a new VM and then proceed to restore to this new VM as if it is a physical machine, whereas if it is backed up as a VM, then you just need to restore it as VM.

Marianne
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Thanks @pkh 

I totally understand that BE and NBU are 2 totally different products, but I thought that they were sharing recent, common development. Like V-Ray.
The V-Ray in NBU 'looks' into the backup stream, catalogs it and therefore knows what is backed up and knows where it is on tape and has no need for disk when restoring individual files from VMware backup. Only for Instant Recovery.

Sad to hear that BE works differently.
I guess the customer will need to decide what is more important - full VM restore or quick individual file restore from tape.

CraigV
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Hi Marianne, It has always worked like this. I think there might have been a product feature request put in during the old Symantec days when this first came out but nothing was done about it. If 1 product in the stack can do it, they should be able to retrofit this along the line for the other. Not to be. So you need as much disk space available for staging as your largest VM. Otherwise get them to buy cheaper iSCSI disk and attach this way. It will work very well if paired with 10GbE network cards. Cheers, and keep well, Craig

Marianne
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Thanks Gents

Not what I was hoping for, but I guess it is what it is.
We need customers to log 'request for enhancement'...

pkh
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Not sure about how NBU works, but basically, BE backs up the entire VM as it is.  If you look at the VM backup set, it does not use .bkf files from which you can restore individual files.  However, from the backup set you can mount the VM and that is the basis of the Instant Recovery feature.

Similiarly, the entire Exchange database is backed up, instead of individual mailboxes.  Hence the need to also stage the Exchange database before an actual restore.